Water supply is a major industry involving the interests of the state and the people. With development of society and the improvement of the people's livelihood, city water supply has been brought forward a higher request. It needed to be timely , accurate and safely to plentifully conduct water supply. If we still continue to use a way of the man-power, the intensity of labor are high , availability is low and the security is difficult to ensure .We must carry out water tower water level under the control of automatic system reforming for this purpose . Programmable Logic Controller (PLC) is applied broadly in industrial control because of high reliability and higher nature price.
The main body of this paper on the control technology is aimed at being popular for at present comparatively, which makes the using of PLC and the sensor to compose water tower control system of permanent water level. Water tower control system after being reformed have realized water tower water level auto-controlling system , long-range supervisory control, and nobody's value guards realization.
Key words：Programmable Logic Controller. water pool water lever. automatically controls
